St. Theodosios was a native of Cappadocia in Asia Minor, now in Turkey, and was born in a.d. 423. He journeyed as a young man to Jerusalem, but on the way went to see the wonder-worker St. Symeon the Stylite, who was clairvoyant through God’s grace, and many things that would come to pass in his later life were foretold to him. He found a monastery with Longinus as his monastic guide and lived in asceticism, fasting, and prayer. After some time he was given obedience for a short time of looking after a church near Bethlehem, but then went further into the desert to live in a cave where he ate coarse foods, and never tasted bread for 30 years.

Many flocked to him in time, and at first reluctantly and then understanding God’s Will, accepted whoever came to live the monastic life sincerely. He founded a large communal or cenobitic monastery in Cathismus near Bethlehem, and is considered one of the main founders of monastic life in Palestine, along with St. Sabas and St. Euthymius the Great. He defended the Faithful against the Eutychian heresy, and worked tirelessly in his God-given tasks until he went peacefully to God in 529 at the age of 105.